mark

Members
 View Profile  See their activity

  • Content

    1,993

  • Joined

  • Last visited

  • Days Won

    2

  • Feedback

    0%

Everything posted by mark

  1. mark
    According to the manual, the warranty period (i.e. the life limit) is 12.5 years. Mark
  2. mark
    I think you might be misremembering. There were never more than a handful of 149 lofts. Most rigging work was done the way it still is, in basements, garages, and in or near a dz packing area. There has never been a requirement for master rigger work to be done in a 149 loft. If there had been, it would have been mentioned in 65.127. Mark
  3. mark
    Part 149 is quoted in full in Poynter Volume 1. It did not require material traceability, only materials of proper strength and quality -- the same standard as required riggers working outside a Part 149 loft, and the same standard as we are held to today. How that could have been assured for a Part 149 loft was a matter between the loft certificate holder and his or her supervising FAA office. Back in the day, almost all riggers legally worked outside a Part 149 loft. Poynter Volume 1, page 31, paragraph 3.300: "The [loft] certificate is of questionable value since it increases duties and responsibilities while it does not increase rights or privileges. . . In the parachute loft, the master rigger must sign off all major repairs. This he must do whether or not the loft has an FAA rating." Mark
  4. mark
    They really are that bad. Truly awful and dangerous. They associate "pull" and "stability." Once you teach that "pull" and "stable" are associated, no amount of explaining will unassociate them. In fact, the more you explain, the worse it will get. A student unstable at pull time will remember only that "pull" and "stable" are things that are both supposed to happen right now. Trying to figure out which is more important means they will more likely work on getting face to earth and/or stopping the spin, because being face to earth and stable is how they have rehearsed and rehearsed their freefall ending. Why not simply: "If you are at or below pull altitude, pull." Why would you need to say more than that? Mark
  5. mark
    How about a Y-shaped seatbelt that has a single-point aircraft attachment at one end, and a quick-eject snap and non-adjustable V-ring on the other? The quick-eject could snap to a hip ring, or to the V-ring on a conventional harnes. Stainless hip rings should work okay; cad-plated might have the plating worn off, although slower than the usual snap & ring combination because the seatbelt snaps would be worn looser than, say, the B-12 snaps on many student leg straps. Mark
  6. mark
    A master rigger would not need approval to install the unit in the main container, say, on the wall between reserve and main. Would that be close enough for testing? Mark
  7. mark
    Reserves bigger than 250 ft^2 and certified after 1994, that is, certified under TSO-C23d or C23f, are allowed to open slower. Some examples are the PD-281, OP-253, and the TR-425 I recently packed in a big-boy rig. How much slower? The short version is 0.01 seconds for every additional square foot over 250, or 1 foot of altitude loss for every square foot over 250. The TR-425 could open in 3 seconds + ((425-250) * 0.01) = 3 seconds + (175 * 0.01) seconds = 3 + 1.75 seconds = 4.75 seconds The owner of the rig was comfortable at belly-fly speed of 160mph. The additional 1.75 seconds means he would need an additional 400 feet or so of altitude in case of an AAD fire. Mark
  8. mark
    Black cherry is my favorite. http://www.uspa.org/SIM/Read/Section4/tabid/166/Default.aspx -Mark
  9. mark
    Current version of TS-100: http://www.pia.com/images/rocketlauncher/PDF/TECHNICAL_STANDARDS/TS100_Final_032715.pdf Mark
  10. mark
    For a harness, there is a logbook entry that identifies the exact article that has been repaired, kept for at least two years. From the logbook entry, the harness can be identified. In the case of a major repair to a ripcord, how could the repaired ripcord be identified from a logbook entry? That is, how could you know it was this ripcord and not that one? Mark
  11. mark
    Maybe that's true for C23b. However, see: C23c/AS8015A, para 2.5.7 and para 4.2.3 C23d/AS8015B, para 2.1.1.g and para 4.2.2 C23f/TS135 rev 1.4, para 2.1.1.g and Table 1 The ripcord is as much as a TSO'd component as the harness or the reserve canopy. I don't think any rig manufacturers would be happy knowing that their TSO markings were on ripcords they didn't make and QC themselves. If one of these "after-market" ripcords were to fail, what would be the procedure to trace others made by the same guy? Mark
  12. mark
    He manufacturers TSO'd items? Mark
  13. mark
    When Optimums first came out and were on tour, I demoed a 143. IIRC, it had about 200 jumps on it. Nice opening and landing. Mark
  14. mark
    How did the master rigger ensure the cable would withstand an end-to-end load of 300# (C23b, f) or 600# (C23c, d)? Mark
  15. mark
    No. That would fall under AC 105-2E para 13.f: "The user of a parachute system may perform simple assembly and disassembly operations necessary for transportation, handling, or storage between periods of use if the parachute’s design simplifies such assembly and disassembly without the use of complex operations." And likestojump is right: quit asking questions to clarify the grey areas unless you're prepared for an answer you don't like. (Not directed at uberchris particularly.) Mark
  16. mark
    In other words, you asked a question for which you already had an answer; you were not asking for information. What exactly was your intention? Mark
  17. mark
    Experiment, part 1a: Regular Sharpies, an "acid-free" Sharpie, and plano china markers. I'll post more photos next week to see if these china markers make stable lines or grease spots. Experiment, part 1b: Same set of markers on ZP. Photos to come. The Sharpies did not bleed as much on the ZP. The first ZP try with plano china markers wiped off pretty easily, so I re-did the sample. Wiping off easily is good or bad, depending on how long you need the mark. Experiment, part 2: Still in process. My plan is to make two identical samples of reserve bridle 2" polyester, one clean and one contaminated with mass quantities of Sharpie ink. Once the ink dries, we'll pull both samples to destruction.
  18. mark
    Changing the harness size would not change the yoke width. Changing the yoke width usually involves sending the rig back to the manufacturer, along with a check for about $3000, and waiting for several weeks or months. On the plus side, you don't have to send the rig to the original manufacturer, you can choose the color of the new yoke, and the harness is likely to be a better fit, too. Mark
  19. mark
    You are right. The cutter should not be exposed. The flaps appear to be closed in the wrong order. The right side flap (with the cutter) should be closed first, with the left side flap on top of it, followed by the top and bottom flaps. Mark
  20. mark
    The current "9" pin is at least the 3rd version. Mark
  21. mark
    Could you say more? I'm not sure this is correct. Some thoughts: . . . The larger pin-loop contact area means more area for friction, but that might be balanced by reduced pressure per square millimeter of contact area with a larger pin. . . . Skyhook pins are substantially larger than conventional pins, but there don't seem to be issues with harder pulls. IIRC, Sunpath currently allows both conventional-pin ripcords (for set-up without RSL) and Skyhook pins (for RSL/Skyhook), without any mention of pull-force issues. . . . This seems similar to the argument (false, I think) that Racers have higher pull forces because they have twice the number of pins compared to most of the other rigs on the market. Mark
  22. mark
    Because it's required by FAR 65.111. [FAR Part 65.111] (c) talks about "maintain or alter", but that doesn't seem to include making one from scratch. Maintain or alter implies that the parachute already exists from some other source. So those folks out there making their own [main] parachutes, are they really violating the regs? No, and there is no regulation limiting the complexity of subassemblies used in the manufacture. Mark
  23. mark
    Because it's required by FAR 65.111. On the other hand, there is no 51% rule as there is for experimental aircraft. If you want to manufacture from subassemblies, there is no prohibition. Mark
  24. mark
    Are these the same as "grease pencils"? Mark
  25. mark
    The risers will soften with use, and eventually it will get easier to pull the slider down. You might also check with the manufacturer to see if it would be okay to wash the risers in hot water, and if so, how and with what precautions. Mark